Tactile keyboard



3, 1968 E. M. HARWELL TACTILE KEYBOARD Original Filed Sept. 19, 1962FIG. 6

INVENTOR. EDWARD M. HARWELL FIG. 5

FIG. 4

ATTORNEY United States Patent 3,396,827 TACTILE KEYBOARD Edward M.Harwell, Houston, Tex., assignor to Litton Business Systems, Inc., acorporation of New York Continuation of application Ser. No. 224,641,Sept. 19, 1962. This application Apr. 25, 1966, Ser. No. 545,166 12Claims. (Cl. 19798) This application is a continuation of applicationSer. No. 224,641, filed Sept. 19, 1962.

The present invention pertains to keyboards. More particularly, it hasto do with a novel and improved keyboard for touch operation. By touchoperation is meant the type of operation in which the operator does notlook at the keyboard in selecting the keys to be depressed, but reliesmerely upon the touch or tactile sense to determine that she will beoperating the intended keys.

The prior art is replete with numerous approaches to structuralmodification of the keys of a keyboard to facilitate touch operation.These prior approaches have involved providing various types of surfacedeformations in the surface of the key whereby the operator will be ableto readily distinguish various keys from another by touch. However,these previous attempts to provide tactile sensing means for touchoperation have never been commercially successful for a variety ofreasons. The major obstacle to their commercial success has been thefact that they have all involved essentially the application of adifferent type of surface deformation for each key of the keyboard. Thishas caused the cost of incorporating such keys in the keyboard to beprohibitive since, in essence, it was necessary to provide a differentkey or key cap for every key position. Further, aside from costconsiderations, the multiplicity of the different types of tactiledevices to which the operator had to become accustomed proved to be soconfusing as to completely negate the intended saving of labor and time.

The present invention has been arrived at after long study andexperimentation. The keyboard of the invention is provided with noveltactile identifying means of two different forms, both forms presentinga touch sensation only along a line. In any given column of thekeyboard, these lines all extend in the same direction. However, in theimmediately adjacent column, the tactile identifying means of the keysare arranged to present a touch sensation to the operator in a directionsubstantially different from the first mentioned direction. This enablesthe operator to readily distinguish one column from the immediatelyadjacent column by touch. Furthermore, in a column the arrangement issuch that each key presents a substantially different touch sensationfrom the keys lying immediately adjacent thereto, whereby the operatorcan readily distinguish the keys within the column from one another.

In the preferred embodiment of the invention disclosed herein, the twotypes of tactile identifying means providing touch sensations along theline are, respectively, spaced protuberances in the form of raised dots,and a raised rib.

In light of the foregoing remarks, it will be seen that a major objectof the invention involves provision of a novel keyboard adapted forimproved touch operation.

A further object is the provision of such a keyboard which can beproduced at relatively low cost.

The primary intended application of the invention is in cash registers.There exists a special need for a commercially acceptable touch keyboardfor cash registers because of the amounts of money directly handled.This is especially true in supermarket operations where personnelturnover is high. The present invention significantly accelerates thetraining of new check-out clerks in cash ice register operation, andalso materially assists trained personnel in maintaining accuracy insuch operation.

Another object of the invention is the provision of such a keyboard inwhich the number of different types of tactile devices is kept to aminimum, whereby an operator can' readily learn how to use such akeyboard, and can use the keyboard, without confusion.

The above and other objects, advantages, and features of the inventionwill become apparent to those skilled in the art from a reading of thefollowing detailed description in conjunction with the accompanyingdrawing in which:

FIG. 1 is a front view of a cash register keyboard in which the presentinvention is incorporated.

FIG. 2 is a sectional view taken on line IIII of FIG. 1.

FIG. 3 is an enlarged sectional View taken on line IIIIII of FIG. 1,showing the spaced, sphericalprotuberance type of tactile indiciaapplied to a key.

FIG. 4 is a similar view taken on line IVIV of FIG. 1, showing thesecond type of tactile indicia comprising an elongated raised ribprovided on a key.

FIG. 5 is a similar view taken on line V--V of FIG. 1, showing thespherical-protuberance type of indicia applied to a key which has acontinuous peripheral upstanding lip or flange.

FIG. 6 is a view similar to FIG. 3, but showing a modified form of theinvention wherein the tactile devices of the invention are provided on atransparent cap which can be slipped over a conventional key.

Referring to FIG. 1 of the drawing, there is shown the digital key bankof a cash register keyboard in which the invention is embodied. The keybank includes three columns of keys, namely a cents or units column 1, adimes or tens column 2, and a dollars or hundreds column 3. As iscustomary, each of the columns of keys comprises nine keys correspondingrespectively to the digital values 1-9.

Three of the keys, namely the seventh key 17 of the units column and thesecond key 22 and the fifth key 25 of the tens columns, are employed ashome keys. They are so identifiable to the touch by being provided witha continuous upstanding ridge or flange about their outer edge. By homekeys is meant that after each ring-up operation, the operator alwaysreturns her fingers to a position contacting at least some of thesethree keys preparatory to entering the price of the next item on thekeyboard.

The top 4 of each key, with the exception of the abovementioned homekeys 17, 22, and 25, is provided with a concave recess 5 to conform toand receive the rounded tip of the operators finger. Home keys 17, 22,and 25 are substantially fiat within their peripheral flanges 40'.

The keys include conventional key stems 41 guided for longitudinalmovement in respective upper and lower keyboard plates 42, 43.Compression springs 44 serve to bias the keys to their normal, raisedunoperated position.

In accordance with the invention, the keys of the abovedescribedconventional keyboard are provided with the two forms of novel tactileindicia now to be described.

One of the two types of indicia comprises two small spaced approximatelyhemispherical protuberances 45 disposed at the opposite sides of the topsurface of the key. It will be understood that the top surface of thekey is that surface which is contacted by the operators fingers for keyoperation. As seen in FIG. 1, certain ones of the keys in each of thecolumns are provided with this type of indicia, namely, in the unitscolumn 1, the first, third, fifth, and ninth keys; and in the tens andhundreds columns 2 and 3, the first, third, fifth, seventh, and ninthkeys. As seen in FIG. 1 in the units and hundreds columns, each pair ofprotuberances 45 lies on a line (or defines a line) extending in a sideto side direction. On the other hand, in the tens column 2, lyingbetween the aforesaid two columns 1 and 3, each pair of spacedhemispherical protuberances 45 lies along a line extending in the foreand aft direction, or in other Words in a directiion perpendicular tothe disposition of the aforesaid horizontal lines of the protuberancesof the units and hundreds columns.

The second type of tactile indicia employed in the preferred embodimentcomprises a continuous raised rib 46 extending across the key betweenthe opposite edges thereof. As best seen in FIG. 1, rib 46 is of uniformthickness. It is also of substantially uniform height, its upper edgebeing concavely curved to conform to the concave recesses provided inthe upper surface of the keys. As shown in FIG. 1, in the units andhundreds columns rib 46 is applied to the fourth and eighth keys, andextends in a sideto-side or horizontal direction parallel to the linesdefined by each pair of the spaced hemispherical protuberances 45applied to other keys in the same two columns.

In the tens column 2, the rib 46 is applied to the sixth key, andextends in the same fore and aft direction as the pairs of protuberances45 applied to other keys of this column.

From the foregoing it will be seen that in any one column of thekeyboard, the two types of indicia employed, i.e., the spacedprotuberances 45 and the continuous rib 46, will each present a tactilesensation to the operator along lines which extend in the same generaldirection. Furthermore, this direction is significantly different asbetween adjacent columns, thereby enabling the operator to readilydistinguish adjacent columns from one another by touch.

If the operator receives a touch sensation along a side to side linebisecting the key, she is thereby made aware that she is touching only aunits or hundreds key, and not a tens key, since the latter keys presentonly a fore and aft touch sensation along the median lines of the keys.Parenthetically, it should be noted that because they are separated bythe tens column, the units and the hundreds columns are not likely to bemistaken for one another.

Furthermore, within a given column even though the protuberances 45 andribs 46 respectively present a touch sensation in the same (parallel)directions, the touch sensations they present are readilydistinguishable from each other. The operator can readily feel theinterrupted or discontinuous sensation alforded by the protuberances 45,and distinguish this from the uninterrupted, continuous sensationafforded by the ribs 46.

It has been found unnecessary to provide the novel tactile indicia ofthe invention for every key of the keyboard. The following keys areunprovided with the indicia: the second, sixth and seventh keys of theunits column 1; the second, fourth, and eighth keys of the tens column2; and the second and sixth keys of the hundreds column 3. Despite this,it will be seen from an inspection of FIG. 1 that each and every keywill present a touch sensation significantly and distinguishablydifferent from all the keys adjacent thereto. The fact that each of theabovementi-oned keys is not provided with any special tactile indicia initself serves as a tactile means for differentiating said keys from theadjacent keys.

Additional means are provided to enable the operator to readilydistinguish the dollars column 3 from the other two columns. The returnsprings 44a for the keys of this column are substantially heavier inaction than the return springs for the first two columns. Accordingly,the operator will have to employ a greater force to depress the dollarcolumn keys, and will readily sense this by touch.

Additionally, as seen in FIG. 2 the stems 41a of the 7 elevation fromtheupper keyboard cover plate than the latter. This higher elevation of thetops of the dollar column keys further assists the operator in beingable to distinguish these keys from the other two columns by touch.

The above-described novel tactile indicia of the invention may beincorporated in the keys in any suitable fashion. As shown in FIGS. 3-5,the indicia may be made integral with the key tops. Alternatively, theindicia can be provided in the form of separate elements rigidly securedto conventional key tops in any suitable fashion as by cementing, etc.

A particularly desirable arrangement for incorporating the novel tactileindicia of the invention in existingkeyboards is shown in FIG. 6. Thisinvolves providing a relatively thin key cap 50 adapted to fit over theconventional key top 46. The tactile indicia, i.e., the spacedhemispherical protuberances of FIG. 6 and the raised rib, are formedintegral with cap 50. The latter has a substantially uniform wallthickness and is contoured to conform to the exterior surface shape ofthe conventional key to which it is to be applied. Thus, as shown inFIG. 6 the upper surface of the cap is curved concavely to lie inintimate face-to-face contact with the surface of the conventional keytop. The key cap 50 is preferably made of transparent material to allowthe operator to see the key.

While there has been shown and described above two preferred forms ofthe invention, it will be appreciated that in practice numerousmodifications, refinements, adaptations, etc., can be resorted towithout departing from the spirit and scope of the invention. Forexample, an elongated groove can be provided in the key tops as asubstitute for the raised ribs 46. The principles of the invention canbe applied to more than three columns of a keyboard. It will beunderstood that the principles of the invention can be incorporated innumerous different types of keyboard operated devices, although asstated before the primary intended application is in cash registers. Itis therefore intended that the foregoing disclosure be illustrative onlyand not limitative of the following claims.

I claim:

1. A keyboard: comprising a first pl'uraity of keys each having disposedthereon tactile identification indicia in the form of a pair of spacedsurface deformations;

a second plurality of keys each having disposed thereon tactileidentification indicia in the form of a continuous elongated surfacedeformation;

a plurality of home keys each having disposed thereon special tactileidentification indicia;

a plurality of other keys;

said first plurality of keys, said second plurality of keys, saidplurality of home keys, and said plurality of other keys all beingdisposed in an array including at least three side by side ordinallyarranged columns of at least nine keys each, said nine keys in each ofsaid columns being respectively representative of the digits 1 through9, at least a majority of the keys in each of said columns havingtactile identification indicia disposed thereon, with at least one ofsaid home keys disposed in a first one of said columns and with all theother keys upon which there are disposed tactile identification indiciain said first one of said columns arranged with their tactileidentification indicia disposed along first imaginary and parallellines, with at least one of said home keys disposed in a second one ofsaid columns and with all the other keys upon which there are disposedtactile identification indicia in said second one of said columnsarranged with their tactile identification indicia disposed along secondimaginary and parallel lines which are at an angle with respect to saidfirst imaginary and parallel lines, and with all the keys upon whichthere are disposed tactile identification indicia in a third one of saidcolumns arranged with their tactile identification indicia disposedthereon in a manner and along imaginary lines corresponding to that ofsaid first one of said columns of keys;

said second column of keys being disposed between said first and saidthird columns of keys;

none of said keys in said side by side columns of keys being disposedadjacent another key in the same column having the same tactileidentification indicia thereon;

none of said plurality of other keys being disposed adjacent any otherof said plurality of other keys in any one of said side by side columns;

the disposition of said keys having tactile indicia and said home keysin said array being such that the operator of the keyboard may locatehis fingers thereupon and with respect to particular digits by actilesensation.

2. The keyboard of claim 1, wherein all the keys in said arrayrepresentative of the digits 1, 3, 5, 7, and 9 constitute a first set,and all the keys in said array representative of the digits 2, 4, 6, and8 constitute a second set;

the tactile indicia disposed on those keys of said first set upon whichthere are disposed tactile identification indicia all being of the sameform; and

the tactile indicia disposed on those keys of said second set upon whichthere are disposed tactile identification indicia all being of the sameform and different from the form of the tactile identification indiciadisposed on said first set of keys.

3. The keyboard of claim 2, wherein the form of the indicia on thosekeys of said first set upon which there are disposed tactile indiciabeing spaced surface deformations; and

the form of the indicia on those keys of said second set upon whichthere are disposed tactile indentification indicia being a continuouselongated surface deformation.

4. The keyboard of claim 1, wherein said special tactile identificationindicia disposed on said home keys is in the form of a continuous ribdisposed about the periphery of the key;

said home key disposed in said first one of said columns occupying theposition of the key representative of the digit 7; and

said second one of said columns including two home keys, one occupyingthe position of the key representative of the digit 2 and one occupyingthe key representative of the digit 5.

5. The keyboard of claim 1, wherein at least some of the keys in each ofsaid columns of keys are from said plurality of other keys.

6. The keyboard of claim 1, wherein:

said spaced surface deformations comprise two spaced protuberances; and

said elongated surface deformation comprises a raised rib.

7. The keyboard of claim 1, wherein:

said angle is ninety degrees.

8. The keyboard according to claim 1, wherein:

the keys of said first and said second columns are disposed at a firstlevel, and the keys of said third column are disposed at a second levelwhich is higher than said first level.

9. A keyboard: comprising a first plurality of keys each having disposedthereon tactile identification indicia in the form of a pair of spacedsurface deformations;

a second plurality of keys each having disposed thereon tactileidentification indicia in the form of a continuous elongated surfacedeformation;

a plurality of home keys each having disposed thereon special tactileidentification indicia;

a plurality of other keys;

said first plurality of keys, said second plurality of keys, saidplurality of home keys and said plurality of other keys all beingdisposed in an array including at least three side by side ordinallyarranged columns of nine keys each, the nine keys in each of saidcolumns being respectively representative of the digits 1 through 9, atleast a majority of the keys in each of at least two adjacent ones ofsaid columns being from said first and second pluralities of keys, withat least one of said home keys disposed in a first one of said columns,with all the other keys from said first and second pluralities of keysthat are disposed in said first one of said two columns being arrangedwith their tactile identification indicia extending in a firstdirection, and with all the other keys from said first and secondpluralities of keys that are disposed in a second one of said columnsbeing arranged with their tactile identification indicia disposed alongimaginary and parallel lines which are at an angle with respect to saidfirst direction; none of said keys in said side by side columns of keysbeing disposed adjacent another key in the same column having the sametactile identification indicia thereon;

none of said plurality of other keys being disposed adjacent any otherof said plurality of other keys in any one of said side by side columns;

the disposition of said keys having tactile indicia and said home keysin said array being such that the operator of the keyboard may locatehis fingers thereupon and with respect to particular digits by tactilesensation.

10. The keyboard of claim 9, wherein:

said second column includes a pair of home keys.

11. The keyboard according to claim 9, wherein:

said angle is ninety degrees.

12. The keyboard according to claim 9, wherein:

the keys of the leftmost column of said three columns of keys aredisposed at a level which is higher than the level of the keys of theother two columns.

References Cited UNITED STATES PATENTS 662,834 11/ 1900 Tcherkassov197-98 695,251 3/1902 Vida-l 197-100 726,107 4/ 1903 Stanton 197-98825,845 7/ 1906 Landenbach 197-98 1,148,721 8/1915 Scott 197-1021,718,694 6/ 1929 Kurowski 197-102 1,823,130 9/1931 Smith 197-982,261,115 11/1941 Hofgaard 197-100 2,585,699 2/1952 Streng 197-982,628,030 2/1953 Taylor 35-5 2,351,541 6/1944 Placke 197-133 2,892,2666/ 1959 Tomkins 35-5 ROBERT E. PULFREY, Primary Examiner.

E. T. WRIGHT, Assistant Examiner.

1. A KEYBOARD: COMPRISING A FIRST PLURALITY OF KEYS EACH HAVING DISPOSEDTHEREON TACTILE IDENTIFICATION INDICIA IN THE FORM OF A PAIR OF SPACEDSURFACE DEFORMATIONS; A SECOND PLURALITY OF KEYS EACH HAVING DISPOSEDTHEREON TACTILE INDENTIFICATION INDICIA IN THE FORM OF A CONTINUOUSELONGATED SURFACE DEFORMATION; A PLURALITY OF HOME KEYS EACH HAVINGDISPOSED THEREON SPECIAL TACTILE IDENTIFICATION INDICIA; A PLURALITY OFKEYS, SAID SECOND PLURALITY OF SAID FIRST PLURALITY OF KEYS, SAID SECONDPLURALITY OF KEYS, SAID PLURALITY OF HOME KEYS, AND SAID PLURALITY OFOTHER KEYS ALL BEING DISPOSED IN AN ARRAY INCLUDING AT LEAST THREE SIDEBY SIDE ORDINALLY ARRANGED COLUMNS OF AT LEAST NINE KEYS EACH, SAID NINEKEYS IN EACH OF SAID COLUMNS BEING RESPECTIVELY REPRESENTATIVE OF THEDIGITS "1" THROUGH "9," AT LEAST A MAJORITY OF THE KEYS IN EACH OF SAIDCOLUMNS HAVING TACTILE INDENTIFICATION INDICIA DISPOSED THEREON. WITH ATLEAST ONE OF SAID HOME KEYS DISPOSED IN A FIRST ONE OF SAID COLUMNS ANDWITH ALL THE OTHER KEYS UPON WHICH THERE ARE DISPOSED TACTILEINDENTIFICATION INDICA IN SAID FIRST ONE OF SAID COLUMNS ARRANGED WITTHEIR TACTILE INDENTIFICATION INDICIA DISPOSED ALING FIRST IMAGINARY ANDPARALLEL LINES, WITH AT LEAST ONE OF SAID HOME KEYS DISPOSED IN A SECONDONE OF SAID COLUMNS AND WITH ALL THE OTHER KEYS UPON WHICH